摘要 |
A compound of the formula: <IMAGE> [wherein R is dimethylamino or 1-pyrrolidinyl; R1 and R2 each is hydrogen or C1-C3 alkyl; R3 is hydrogen, C1-C3 alkyl (optionally substituted by one member selected from the group consisting of cyano, C1-C3 alkoxy, phenyl, and 5- or 6-membered heterocyclic group), C3-C6 cycloalkyl, C2-C5 alkenyl (optionally substituted by one member selected from the group consisting of C1-C3 alkoxy, phenyl, and phenoxy), C6-C10 aryl (optionally substituted by one or two members selected from the group consisting of hydroxy, halogen, nitro, sulfamoyl, C1-C3 alkyl, C1-C3 alkoxy, C1-C3 alkanoyl, C2-C4 alkoxycarbonyl, C2-C4 dialkylamino, and C1-C3 alkanesulfonyl), or 5- or 6-membered heterocyclic group (optionally substituted by one member selected from the group consisting of oxo, halogen, C1-C3 alkyl, and C1-C3 alkoxy); and X is oxygen or sulfur] and its pharmaceutically acceptable acid addition salts is useful as histamine H2 blockers. |